Web feeding mechanism for package forming machines



May 13, 1952 J. G. VERGOBBI WEB FEEDING MECHANISM FOR PACKAGE FORMING MACHINES Filed Oct. 1., 1948 'INVENTOR. 6 4 4 JMQM M ATTORNEV Patented May 13, 1952 WEB FEEDING MECHANISM FOR PACKAGE FORMING MACHINES John G. Vergobbi, Quincy, Mass., assignor to Pneumatic Scale Corporation, Limited, Quincy, Mass, a corporation of Massachusetts Application October 1, 1948, Serial No. 52,257

Claims. 1

This invention relates to web feeding mechanism particularly adapted for use in a package forming machine.

The invention has for an object to provide a novel and improved Web feeding mechanism wherein provision is made for controlling the leading portion or free end of a relatively thin, lightweight flexible web of sheet material as it is being advanced into a predetermined position, in a simple and highly efficient manner.

With this general object in view and such others as may hereinafter appear the invention consists in the web feeding mechanism and in the various structures, arrangements and combinations of parts hereinafter described and particularly defined in the claims at the end of this specification.

In the drawings illustrating the preferred embodiment of the invention, Fig. 1 is a side elevation, partly in cross-section, of a package forming machine provided with web feeding mechanism embodying the present invention; Fig. 2 is a front elevation as viewed from the line 2-2 of Fig. 1; and Fig. 3 is an elevation of the web feeding mechanism as viewed from the line 3--3 of Fig. 1.

In general the present invention contemplates novel web feeding mechanism particularly adapted for feeding a web of relatively thin lightweight fiexible sheet material from a supply thereof and into operative position to be severed to form an individual sheet or blank of container forming material. The invention is herein illustrated .as embodied in a container forming machine for forming a lined carton in which the sheet material is fed into operative position to be wrapped about a forming block to form a bag or inner liner for a package. Inasmuch as the de-- tails of such container forming machines are well known and of themselves con titute no part 01' the present invention, only sufficient portions of such machines are herein illustrated and described to enable the present invention to be understood.

Prior to the present invention difficulty has been encountered in feeding relatively thin lightweight sheet material such as a thin paper web, for example. into a definite and predetermined position relative to the usual blank forming cutter and to the forming block, because of the relatively light weight and instability of the 'material and, in practice, the free end of such material often would curl up, wrinkle. or fold over when it engaged the supporting elements upon which it was supported as it was advanced, thus interrupting the successful and practical operation of the machine.

In accordance with the present invention, provision is made for controlling the movement of the leading portion of the sheet material to be fed as it i being advanced by causing a stream of air to flow along the underside of the leading portion of the sheet in the direction of move-- ment of the sheet. The air stream is directed thereby in a direction parallel to the under-' surface of the sheet and thus insuring the proper relation of the sheet to the supporting elements upon which it is being advanced.

Referring now to the drawings, It represents a forming block or mandrel forming a part of a container forming machine having a plurality of such forming blocks, only one of which is shown. The blocks are arranged to be intermittently moved to the various lining and carton forming stations of the machine. In general, in the operation of such machines, the sheet material is advanced beneath the forming block and severed to form a lining blank, and the lining blank is then folded about the forming block to form a tube. At a succeeding station of operation, portions of the lining blank extending beyond the end of the forming block are folded and sealed to form the bottom end of the lining bag. At subsequent stations of the machine an outer blank or carton may be wrapped about the lining bag on the block in a similar manner, whereupon the compo ite liner and carton may be stripped from the forming block ready to be filled and the top sealed.

In the illustrated embodiment of the invention, a web of sheet material 12 is unwound from a supply roll it thereof by a pair of intermittently operated cooperating rollers 16, Iii and fed into operative position beneath the forming block In and on top of supporting elements herein shown as comprising vertically reciprocal blank supporting and folding means of well-known construction including a bottom plate 20 and pairs of side brackets 22 and 24 arranged to be subsequently elevated to wrap the blank about the bottom and two sides of the block If! as illustrated in Fig. 2. According to the present invention the u per surfaces of the brackets 22 and 24 are provided with upstanding spaced parallel ribs bridging the brackets and extending in the direction of web movement. As shown in Fig. 2 these ribs may be provided by attaching wires or rods 21 to the brackets 22 and 24 as by welding or brazing. In practice the bottom plate 20 is elevated to present and retain the blank in firm engagement with the channels between the ribs.

undersurface of the block, while the side brackets 22 and 24, and rods 21 continue upwardly to wrap the blank against the sides of the block, leavin or contiguous relation and sealed to form a tubular bag portion, and then the extended end portions of the tube are folded and sealed to close the bottom of the bag inthe usual manner.

The web feed rollers I6, It may and preferably will be intermittently operated to feed a predetermined length of the thin web material onto the foldingplates each cycle of operation, and provision is then made for severing the leading portion of the web to form a lining blank. As herein shown, the severing mechanism may comprise a pair of cooperating cutting elements including a fixed knife blade 3E) and a movable blade 32 as illustrated in Fig. 1.

In accordance with the present invention provision is made for controlling the leadingor forward portion of the web extending beyond the feed rollers l6, id to maintain the same extended in a substantially horizontal position parallel to the'supporting elements comprising the folding brackets and rods and, as herein shown, this is accomplished by projecting a plurality of streams of *air along the underside of the sheet between it and the brackets and along the channels between'ribs 21 in the direction of movement of the sheet and parallel thereto as it is being fed forward by the feed rollers l5, l8. he compressed air may be supplied from any usual or preferred source, and as herein shown, is arranged to pass through a plurality of relatively small spaced tubes or jets 34 connected at one end to an air supply pipe 38 disposed below and in front of the feed roller l8. The tubes 35 extend upwardly from the supply pipe and are curved around the feed roller l8 and extended horizontally to assume 7 a position parallel to and immediately beneath the web being advanced. As best shown in Fig. 3, the tubes 34 are arranged to fit into spaced front of the cutter blades, as shown.

With this construction it will be observed that in th'e operation of the machine the streams of air projected from the tubes 34 will necessarily pass between the web 12 and brackets 22 and 24, being guided by the ribs 26 to move along the By confining the streams in this manner their velocity is preserved and'turbulence prevented. The velocity of the air streams pass over the brackets 22 and 24.

From the above description of the" preferred embodiment of the invention it will be seen that in the operation of the machine the web of container forming material I2 is intermittently advanced into operative position to dispose the leading blank forming portion of the web beneath the forming block In and into operative relation to the severing blades 3!], 32 to form successive cut-to-length blank sheets adapted to be wrapped about successive forming blocks In to form the containers and that during the advance of the leading portion of the web beyond the feed rolls l6, It, the web is maintained in a horizontally extended position by the air streams caused to flow between the undersurface of the web and the upper surfaces of the folding elements 20, 22, 24 and 21. The cut-off operation may occur immediately upon the web coming to rest and immediately thereafter the folding elements may be elevatedto perform the wrapping operation. While the air streams may be controlled in any usual or preferred manner to start and stop the fiow'of air in timed relation to the advancement of the web, it will be observed that in the illustrated embodiment of the invention the movable cutter blade 32ais disposed in aposition to cut off or divert the flow of air from the jets 34 during the severing operation and immediately thereafter or simultaneously therewith the folding plates are operated to carrythe severed blank upwardly out of the influence of the air streams when the'jets are subsequently exposed by the cutter blade.

While the present web feedingmechanism may be used with advantage forfeeding and controlling the leading portion of relatively thin, nonrigid lightweight paper, cellophane or other sheet material, it will be apparent that the invention may be used with advantage in feeding heavier and more rigid types of flexible sheet material to assist in controlling the advance of the leading portion. 7

While the preferred embodiment of the invention has been herein illustrated and described, it will be understood thatthe invention may be embodied in other forms within the scope of the following claims. I

Having thus described the invention, what is claimed is:

1. In apparatus of the character described, in

combination, feeding mechanism comprising a' pair of intermittently operated feed rolls arranged to advance a predetermined length of a web container formingmaterial, folding means which the advanced portion of the web is passed, and means for maintaining said advanced portion in a fully extended condition and in operative relation to said folding means during the advancing movement comprising a plurality of air jets arranged to direct a pluralityof streams of air along the undersurface of said. advanced portion substantially parallel to and in .the .direction of movement of the weband upstanding parallel ribs on said means defining channels for said streams of air extending in the direction of movement of'said web.

2. In apparatus of the character. described, in combination, feeding mechanism comprising. a pair of intermittently operated feed rolls-are ranged to advance a predetermined length of a web of container forming material, folding meansover which the advanced portion of the web is passed, and means for maintaining said advanced portion in a fully extended'condition and inoperative relation to said folding means during the advancing operation, comprising a plurality of air jets arranged to' direct a =plurality of streams of air along the undersurface of said advanced portion substantially parallel to and in the direction of movement of the web,

and means for interrupting said air streams after said predetermined length has been advanced and upstanding parallel ribs on said means defining channels for said streams of air extending in the direction of movement of said web.

3. In apparatus of the character described, in combination, a forming block, feeding mechanism comprising a pair of intermittently operated feed rolls arranged to advance a predetermined length of a web of container forming material, folding means upon which the advanced portion of the web is supported to be subsequently folded about the block, and means for maintaining said advanced portion in a fully extended condition and in operative relation to said folding means during the advancing operation comprising a means for directing a stream of air between the folding means and the undersurface of said advanced portion substantially parallel to and in the direction of movement of the web, and a cutter blade arranged to sever the advanced portion from the web, said blade being arranged to interrupt the air streams during the severing operation and upstanding parallel ribs on said means defining channels for said streams of air extending in the direction of movement of said Web.

4. In apparatus of the character described, in combination, a pair of cooperating feed rolls comprising an upper and a lower roll arranged to advance a predetermined length of a web of flexible container forming material, means spaced from said rolls to receive and support material advanced by said rolls, and means for maintaining the advanced portion of the Web in its fully extended condition during the advancing movement comprising a plurality of spaced air pipes arranged to direct a plurality of streams of air along the underside of said advanced portion substantially parallel to and in the direction of movement of said web, said lower feed roll having a plurality of spaced peripheral grooves through which said air pipes are extended to bridge the space between said rolls and said material receiving and supporting means, said pipes being disposed along and in contact with the underside of the advanced portion of the web.

5. In mechanism for feeding a web of flexible sheet material, in combination, supporting means to receive said web, a plurality of upstanding spaced parallel ribs on said supporting means and extending in the direction of movement of said web, the crests of said ribs lying substantially in a single plane, means for advancing the Web to and over said supporting means, and means for directing a plurality of streams of air along the undersurface of said advancing web in the direction of movement thereof and through the channels defined by said ribs whereby said web is pneumatically urged against the crests of said ribs and caused to lie thereover in a substantially flat and planar condition.

JOHN G. VERGOBBI.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,020,821 Hesser Mar. 19, 1912 1,161,346 Schmidt Nov. 23, 1915 1,378,581 Bernotow May 17, 1921 2,037,806 Little Apr. 21, 1936 2,261,972 Matthews Nov. 11, 1941 2,441,912 Streich May 18, 1948 2,454,762 Belluche Nov. 30, 1948 FOREIGN PATENTS Number Country Date 363,816 Great Britain Dec. 31, 1931 

